in our BES 4.0.5 environment (approx 200 users, exchange 2003 SP2) we see a LOT of wireless calendar sync problems, most of them including disappearing calender items on the BB!

most of them (though not all) have delegates looking into their calendars, invitations get sent out, accepted, declined, or updated, and then... lost.

We have constantly users complaining about non-synchronised calender entries, and there does not seem to be one single point to start working with. Also strange issues likes "??????" question marks into the subject fields, meetings that send a "decline" message to another user while being accepted (!), meetings that get updated and accepted but then get deleted on the BB... i can go on and on and on.

Are the entries still showing up in Exchange?
Do the users see the same thing in OWA as they do with their Outlook client?
Do you have any users using the Desktop Manager?
Is everyone using 4.x HH software?
Is there anyone that isn't having the problem at all?

Are the entries still showing up in Exchange?
Do the users see the same thing in OWA as they do with their Outlook client?
Do you have any users using the Desktop Manager?
Is everyone using 4.x HH software?
Is there anyone that isn't having the problem at all?

Are the entries still showing up in Exchange?
>> most of the calendar entries do show up correctly in their Outlook 2000 client

Do the users see the same thing in OWA as they do with their Outlook client?
>> OWA is not active (yet) in our environment (unfortunately...)

Do you have any users using the Desktop Manager?
>> normally no user should be using the desktop manager. All devices are able to sync wireless. However, is there a way to investigate whether as to someone actually IS using the desktop manager? (logfiles??) We have more than 200 users so I can't check it individually

Is everyone using 4.x HH software?
>> All devices have the device software 4.x

Is there anyone that isn't having the problem at all?
>> luckily, it's only a relative small core of users that *report* the problems on a regular basis (read: daily on my private phone). However, i cannot exclude anyone from having this issues... some have the issue but only use their BB'ies for e-mail

i'm suspecting that it has something to do with one of the many, many lines I see in the MAGT_ logs:

MAPIMailbox:: xxxxx - OpenEntry (0x8004010f) failed

where xxxxx can be one of the following:
- OpenMessage
- HandleObjectModifiedNotification
- UpdateRimMessageState

I found a related article on BB.com (KB03567), however it also says, "This is a previously reported issue that has been escalated internally to our development team. No resolution time frame is currently available."

I would try an Outlook 2003 Client and possibly upgrading 4.0 SP7 ... see what happens; try to track down any similiarity between users having the problem and call for TSupport at that point if you have no patterns developing.